Sheet material



FIG. 1 is a perspective view showing the new design for a sheet material;

FIG. 2 is a top view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a front view thereof; and,

FIG. 5 is a side view thereof.

The broken line perimeter drawn within the outer structure of the sheet material represents the boundaries of the claim and forms no part thereof. The portions of the sheet material surrounding the inner boundary of the design that are drawn in broken lines represent parts of the article that form no part of the claimed design. 

CLAIM The ornamental design for a sheet material, as shown and described. 